Kirk McConer was arrested and jailed while talking to a friend outside a convenience store, where he had just purchased a soda. Tyrone Hightower was arrested and jailed after sitting in his car in the parking lot of a nightclub, as he waited to make sure his friends were admitted to the club. And Jacob Manyong was stopped and placed under arrest after the back tire of his car barely crossed the property of a private business, as he drove out of an adjacent public lot.

The charges against McConer, Hightower, and Manyong? Trespassing.

Although the charges against each of them were eventually dropped, memories of the experience still linger—so much so that each of them remains fearful that he could be victimized again at any moment.

And they’re scared for good reason. Their respective ordeals were the product of a practice introduced by the Grand Rapids Police Department decades ago, which relies on the use of generalized “No Trespass Letters” to justify arrests for criminal trespassing on commercial property. But more to the point, the policy gives police in Michigan’s second-largest city an excuse to stop and search people immediately based on nothing more than a gut reaction to the way someone looks or acts—without bothering to determine whether the person is actually trespassing.

Here’s how it works: Grand Rapids police officers solicit business owners in select “high-crime” neighborhoods and ask them to sign a No Trespass Letter, stating that they do not want unauthorized people on their property and that they will cooperate with any efforts to prosecute trespassers. The signed letter, valid for one year, is then placed on file with the police department and can be renewed.

So far, so good, but here’s the rub:

According to Grand Rapids police officials, the signed letter allows officers to stop and arrest people for trespassing at the business in question—even while the business is open—whenever the officer thinks the person is on the property without a “legitimate business purpose.” In other words, cops are given unrestricted discretion to decide who does and does not belong on the property of an open business, without ever talking to the business owner or any employee to find out why the person is on the property, how long they’ve been there, and whether the person is welcome on the premises.

Which raises the question: How can Grand Rapids patrol officers possibly know who is and is not a trespasser without first determining whether the business has authorized the person to be there?

The short answer is: They can’t. But if the business has a No Trespass Letter on file, police officers are given carte blanche to make that very judgment.

The results have been predictably disturbing.

Between 2011 and 2013, the Grand Rapids Police Department either cited or arrested approximately 560 people for trespassing on business property, pursuant to the trespassing-letter policy. In a city in which black people make up roughly 20 percent of the population, 59 percent of those detained for trespassing under this policy were black. Perhaps even more telling is the fact that African-Americans are more than twice as likely as whites to be arrested, rather than simply ticketed, when the police bring charges for trespassing on the property of an open business in Grand Rapids.

To make matters worse, police department officials are quite proud of the No Trespassing Letter program, referring to it repeatedly as a “valuable law enforcement tool” that allows the police to stop, question, and, sometimes, search individuals who they would otherwise have no justification for detaining.

That’s why the ACLU and the ACLU of Michigan filed a federal lawsuit against the City of Grand Rapids in May 2013, challenging the constitutionality of the No Trespass Letter policy on the grounds that it violates the Fourth Amendment and gives unfettered discretion to police officers in the enforcement of the trespassing law. The case is still pending.

If the Grand Rapids policy sounds familiar, it should. Such an approach is just one example of police departments around the country using aggressive enforcement of low-level crimes in communities of color—known as “broken windows” or “order maintenance” policing—purportedly to prevent more serious crimes. This is the policing model touted by the likes of Chief William Bratton in New York City and Chief Ed Flynn in Milwaukee, who have doubled down on their commitment to reducing various low-level crimes in certain areas, offenses such as disorderly conduct, vagrancy, and, yes, trespassing.

These policing practices continue in many U.S. cities, even though it was the attempted enforcement of low-level crimes in Ferguson (jaywalking), Staten Island (selling loose cigarettes), and Milwaukee (sleeping in a public park) that led to the deaths of Michael Brown, Eric Garner, and Dontre Hamilton, respectively, at the hands of police officers in 2014.

Even in smaller cities like Miami Gardens, Florida, broken windows policing has wreaked havoc on the very communities that are supposed to benefit from it.

Under a policy similar to Grand Rapids’ No Trespass Letters, Miami Gardens’ police officers were given the discretion to identify individuals who they believed were trespassing on the property of open businesses as part of the department’s “Zero Tolerance Zone Trespassing” program. As detailed in a recent “This American Life” episode, it was African-Americans, yet again, who bore the brunt of the program’s implementation. Neither business patrons nor store employees were safe from Miami Gardens’ officers, who embarked on a terrifying and unnecessary trespass enforcement spree that contributed significantly to the roughly 99,000 total stops made by officers over the course of five years—in a city of only 110,000 people. One African-American man was stopped more than 250 times for suspected trespassing on the property of the convenience store where he worked. More than 60 of those stops resulted in his arrest.

So what’s the takeaway here? Despite the best intentions of law enforcement, broken windows policing can have dire consequences for communities of color, especially when police officers are given broad discretion to enforce certain laws more aggressively in those communities, with little guidance from their superiors and no fear of meaningful consequences in the event that innocent people are swept up—or even killed—in the process.

If police departments are serious about establishing strong, healthy relationships with communities of color based on mutual trust and respect, they will abandon the broken windows approach altogether. Instead, they should work in partnership with community members and experts in the field to determine the best ways to provide responsive, effective police services to the communities most impacted by crime, while also respecting the constitutional rights of everyone they are sworn to serve and protect.

HandsUpUnitedis a collective of politically engaged minds building towards the liberation of oppressed Black, Brown and poor people through education, art, civil disobedience, advocacy and agriculture.